Hi I am using Mac OS X Version 10.8.2 and the Adobe Acrobat Pro XI Trial Version, using the combine files option I get the following error: "Acrobat does not support the conversion of one or more of your files to PDF. Please remove these files or go to Settings and choose the PDF Portolio option." I have .doc and .docx files to convert, I do not have MS Office installed on this computer. Is that the problem? Do I need to have office installed to convert the files? Thanks.